Dealing with Changing Public IP Addresses in BorderManager

Problem

A Forum reader recently asked:

"I found out that a few months down the road I'll be dealing with new public IP addresses. Can you recommend anything to read? Are there any gotchas, or do you have other sage words for me? The site is moving; we'll be using the same ISP, but it has to be reprovisioned for various reasons."

And here's the response from Caterina Luppi ...

Solution

You'll have your hands full. If your server is only doing proxy for your users, the major issue are the filters that will have to be changed to reflect the new address. If you're using SSL, reverse proxy, internal mail servers, internal web servers, VPN etc, you're in for a larger amount of work.

First of all, make sure you don't take shortcuts in the process, since they don't pay off.

Once you've got the new addresses,

1. Disable filtering in inetcfg.

2. Bind the new addresses to your public interface.

3. Change the default gateway and DNS servers and make sure that basic routing works (you can ping the internet, resolve names etc).

4. If that works, configure NAT on the public binding and make sure that a workstation can access the Internet.